Efficacy and safety of VEPTR instrumentation for progressive spine deformities in young children without rib fusions

Instrumentation failure following pediatric spine deformity growth-sparing surgery using traditional growing rods or vertical expandable prosthetic titanium ribs

BACKGROUND

Instrumentation failure (IF) is a major complication associated with growth-sparing surgery for pediatric spinal deformities; however, studies focusing on IF following each surgical procedure are lacking. We aimed to evaluate the incidence, timing, and rates of unplanned return to the operating room (UPROR) associated with IF following each surgical procedure in growth-sparing surgeries using traditional growing rods (TGRs) and vertical expandable prosthetic titanium ribs (VEPTRs).

METHODS

We reviewed 1,139 surgical procedures documented in a Japanese multicenter database from 2015 to 2017. Of these, 544 TGR and 455 VEPTR procedures were included for evaluation on a per-surgery basis. IF was defined as the occurrence of an implant-related complication requiring revision surgery.

RESULTS

The surgery-based incidences of IF requiring revision surgery in the TGR and VEPTR groups were 4.3% and 4.0%, respectively, with no significant intergroup difference. Remarkably, there was a negative correlation between IF incidence per surgical procedure and the number of lengthening surgeries in both groups. In addition, rod breakage in the TGR group and anchor-related complications in the VEPTR group tended to occur relatively early in the treatment course. The surgery-based rates of UPROR due to IF in the TGR and VEPTR groups were 2.0% and 1.5%, respectively, showing no statistically significant difference.

CONCLUSIONS

We found that IF, such as anchor related-complications and rod breakage, occurs more frequently earlier in the course of lengthening surgeries. This finding may help in patient counseling and highlights the importance of close postoperative follow-up to detect IF and improve outcomes.

Effects of spinal deformities on lung development in children: a review

Scoliosis before the age of 5 years is referred to as early-onset scoliosis (EOS). While causes may vary, EOS can potentially affect respiratory function and lung development as children grow. Moreover, scoliosis can lead to thoracic insufficiency syndrome when aggravated or left untreated. Therefore, spinal thoracic deformities often require intervention in early childhood, and solving these problems requires new methods that include the means for both deformity correction and growth maintenance. Therapeutic strategies for preserving the growing spine and thorax include growth rods, vertically expandable titanium artificial ribs, MAGEC rods, braces and casts. The goals of any growth-promoting surgical strategy are to alter the natural history of cardiorespiratory development, limit the progression of underlying spondylarthrosis deformities and minimize negative changes in spondylothorax biomechanics due to the instrumental action of the implant. This review further elucidates EOS in terms of its aetiology, pathogenesis, pathology and treatment.

Contraindications to magnetically controlled growing rods: consensus among experts in treating early onset scoliosis

PURPOSE

The purpose of this study was to describe contraindications to the magnetically controlled growing rod (MCGR) in patients with early onset scoliosis (EOS) by establishing consensus amongst expert surgeons who treat these patients frequently.

METHODS

Nine pediatric spine surgeons from an international EOS study group participated in semi-structured interviews via email to identify factors that influence decision making in the use of MCGR. A 39-question survey was then developed to specify these factors as contraindications for MCGR-these included patient age and size, etiology, medical comorbidities, coronal and sagittal curve profiles, and skin and soft tissue characteristics. Pediatric spine surgeons from the EOS international study group were invited to complete the survey. A second 29-item survey was created to determine details and clarify results from the first survey. Responses were analyzed for consensus (> 70%), near consensus (60-69%), and no consensus/variability (< 60%) for MCGR contraindication.

RESULTS

56 surgeons of 173 invited (32%) completed the first survey, and 64 (37%) completed the second survey. Responders had a mean of over 15 years in practice (range 1-45) with over 6 years of experience with using MCGR (range 2-12). 71.4% of respondents agreed that patient size characteristics should be considered as contraindications, including BMI (81.3%) and spinal height (84.4%), although a specific BMI range or a specific minimum spinal height were not agreed upon. Among surgeons who agreed that skin and soft tissue problems were contraindications (78.6%), insufficient soft tissue (98%) and skin (89%) to cover MCGR were specified. Among surgeons who reported curve stiffness as a contraindication (85.9%), there was agreement that this curve stiffness should be defined by clinical evaluation (78.2%) and by traction films (72.3%). Among surgeons who reported sagittal curve characteristics as contraindications, hyperkyphosis (95.3%) and sagittal curve apex above T3 (70%) were specified. Surgeons who indicated the need for repetitive MRI as a contraindication (79.7%) agreed that image quality (72.9%) and not patient safety (13.6%) was the concern. In the entire cohort, consensus was not achieved on the following factors: patient age (57.4%), medical comorbidities (46.4%), etiology (53.6%), and coronal curve characteristics (58.9%).

CONCLUSION

Surgeon consensus suggests that MCGR should be avoided in patients who have insufficient spinal height to accommodate the MCGR, have potential skin and soft tissue inadequacy, have too stiff a spinal curve, have too much kyphosis, and require repetitive MRI, particularly of the spine. Future data-driven studies using this framework are warranted to generate more specific criteria (e.g. specific degrees of kyphosis) to facilitate clinical decision making for EOS patients.

LEVEL OF EVIDENCE

Level V-expert opinion.

Comparison of surgical interventions for the treatment of early-onset scoliosis: a systematic review and meta-analysis

OBJECTIVE

Several growth-preserving surgical techniques are employed in the management of early-onset scoliosis (EOS). The authors' objective was to compare the use of traditional growing rods (TGRs), magnetically controlled growing rods (MCGRs), Shilla growth guidance techniques, and vertically expanding prosthetic titanium ribs (VEPTRs) for the management of EOS.

METHODS

A systematic review of electronic databases, including Ovid MEDLINE and Cochrane, was performed. Outcomes of interest included correction of Cobb angle, T1-S1 distance, and complication rate, including alignment, hardware failure and infection, and planned and unplanned reoperation rates. The percent changes and 95% CIs were pooled across studies using random-effects meta-analysis.

RESULTS

A total of 67 studies were identified, which included 2021 patients. Of these, 1169 (57.8%) patients underwent operations with TGR, 178 (8.8%) Shilla growth guidance system, 448 (22.2%) MCGR, and 226 (11.1%) VEPTR system. The mean ± SD age of the cohort was 6.9 ± 1.2 years. The authors found that the Shilla technique provided the most significant improvement in coronal Cobb angle immediately after surgery (mean [95% CI] 64.3% [61.4%-67.2%]), whereas VEPTR (27.6% [22.7%-33.6%]) performed significantly worse. VEPTR also performed significantly worse than the other techniques at final follow-up. The techniques also provided comparable gains in T1-S1 height immediately postoperatively (mean [95% CI] 10.7% [8.4%-13.0%]); however, TGR performed better at final follow-up (21.4% [18.7%-24.1%]). Complications were not significantly different among the patients who underwent the Shilla, TGR, MCGR, and VEPTR techniques, except for the rate of infections. The TGR technique had the lowest rate of unplanned reoperations (mean [95% CI] 15% [10%-23%] vs 24% [19%-29%]) but the highest number of planned reoperations per patient (5.31 [4.83-5.82]). The overall certainty was also low, with a high risk of bias across studies.

CONCLUSIONS

This analysis suggested that the Shilla technique was associated with a greater early coronal Cobb angle correction, whereas use of VEPTR was associated with a lower correction rate at any time point. TGR offered the most significant height gain at final follow-up. The complication rates were comparable across all surgical techniques. The optimal surgical approach should be tailored to individual patients, taking into consideration the strengths and limitations of each option.

Early-onset scoliosis: a narrative review

Early-onset scoliosis (EOS) is defined as any spinal deformity that is present before 10 years old, regardless of etiology.

Deformity must be evaluated based on the intercorrelation between the lungs, spine, and thorax.

Curvatures of early-onset have increased risk of progression, cardiorespiratory problems, and increased morbidity and mortality.

Progression of the deformity may produce thoracic insufficiency syndrome, where a distorted thorax is unable to support normal respiratory function or lung growth.

Management and treatment of EOS should pursue a holistic approach in which the psychological impact and quality of life of the patient are also taken into consideration.

Growth-friendly surgical techniques have not met the initial expectations of correcting scoliotic deformity, promoting thoracic growth, and improving pulmonary function.

Wound-Related Complication in Growth-Friendly Spinal Surgeries for Early-Onset Scoliosis-Literature Review

Background: The treatment for early-onset scoliosis (EOS) is one of the most challenging for pediatric orthopedics. Surgical treatment is often necessary, and wound problems and surgical site infections (SSIs) are common, with potentially severe complications in these patients. The aim of the study was to review current literature according to this complication. Methods: PubMed, Cochrane Library, and Embase were systematically searched for relevant articles by two independent reviewers in January 2022. Every step of the review was done according to PRISMA guidelines. Results: A total of 3579 articles were found. Twenty four articles were included in this systematic review after applying our inclusion and exclusion criteria. EOS surgery has a varying but high rate of wound-related problems (on average, 15.5%). Conclusion: The literature concerning the definitions, collection, and interpretation of data regarding EOS wound-related complications is often difficult to interpret. This causes problems in the comparison and analysis. Additionally, this observation indicates that data on the incidence of SSI may be underestimated. Awareness of the high rate of SSI of EOS surgery is crucial, and an optimal strategy for prevention should become a priority.

Complications in growth-friendly spinal surgeries for early-onset scoliosis: Literature review

BACKGROUND

The treatments for early-onset scoliosis (EOS), defined as curvature of the spine with onset before 10 years of age, continue to pose a great challenge for pediatric orthopedics. The treatment goals for EOS include minimizing spinal deformity while maximizing thoracic volume and pulmonary function. Different surgical techniques have different advantages and drawbacks; however, the two major concerns in the management of EOS are repeated surgeries and complications.

AIM

To review the current literature to assess the safety of EOS surgical treatment in terms of the rate of complications and unplanned surgeries.

METHODS

In January 2021 two independent reviewers systematically searched three electronic medical databases (PubMed, the Cochrane Library, and Embase) for relevant articles. Every step of the review was done according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Due to the heterogeneity of articles and topics after data analysis, a descriptive (synthetic) analysis was performed.

RESULTS

A total of 2136 articles were found. Forty articles were included in this systematic review, after applying our inclusion and exclusion criteria. EOS surgery has a varying but high rate of complications. The most frequent complications were categorized as implant (54%), general (17%), wound (15%) and alignment (12%). The rate of complications might have been even higher than reported, as some authors do not report all types of complications. About 54% of patients required unplanned surgeries due to complications, which comprised 15% of all surgeries.

CONCLUSION

The literature concerning the definitions, collection, and interpretation of data regarding EOS surgery complications is often difficult to interpret. This creates problems in the comparison, analysis, and improvement of spine surgery practice. Additionally, this observation indicates that data on the incidence of complications can be underestimated, and should be interpreted with caution. Awareness of the high rate of complications of EOS surgery is crucial, and an optimal strategy for prevention should become a priority.

Efficacy of distal pedicle screw fixation as a caudal foundation in VEPTR growing rod constructs for early onset scoliosis

PURPOSE

Surgical treatment of Early Onset Scoliosis (EOS) is challenging. Stable and robust foundations are vital. We have assessed a small cohort of patients with a rib-based proximal fixation and a pedicle screw-based distal foundation for a distraction based growing rod system.

METHOD

This is a single center study in a tertiary spinal deformity unit with a catchment population of over 6 million. We performed a retrospective radiographic evaluation of 15 patients with EOS treated with Vertical Expandable Titanium Prosthetic Rib (VEPTR) implant between 2007 and 2017. The review of medical records and imaging data was performed to identify growth of the spine and complications with pedicle screws.

RESULTS

There were ten male and five female patients with an average age at index surgery of 4yrs 11 months. Mean length of follow-up was 6 yrs 9 months. Serial radiographs revealed improvements in mean Cobb angle of 12 degrees, T1-T12 height of 29 mm and T1-S1 height of 48 mm with no deterioration in distal LIV tilt angle. We report that none of these patients had any complications related to their pedicle screws including cut-out.

CONCLUSION

We report a technique which is efficacious and provides a mechanically robust distal fixation for VEPTR lengthening in early onset scoliosis.

Early Complications in Vertical Expandable Prosthetic Titanium Rib and Magnetically Controlled Growing Rods to Manage Early Onset Scoliosis

OBJECTIVES

The aim of this study is to examine whether surgical treatment of early onset scoliosis (EOS) with magnetically controlled growing rods (MCGRs) or a vertical expandable prosthetic titanium rib (VEPTR) resulted in fewer short-term (24 months) complications and reoperations.

BACKGROUND

EOS is a challenging problem for spine surgeons that has been managed with different growth-friendly instrumentation systems. Although rib-based devices encourage spinal growth via regular lengthening, the high rate of complications and reoperations leads us to use spine-based devices such as MCGRs to mitigate this concern.

METHODS

A total of 35 EOS patients were included in the study. Twenty patients were included in the VEPTR group, and 15 patients were included in the MCGR group. Demographic data and 2 years of postoperative complications and reoperations were reviewed retrospectively. As secondary outcomes, radiographic outcomes were reported preoperatively and 1 year after surgery. Indications for this technique and complications were collected from the charts.

RESULTS

Demographic data showed no significant differences between the 2 groups. Significant differences were found in the complications rate at 2 years, with 65% complications in the VEPTR group and 13.3% complications in the MCGR group (P < .001). The reoperation rate at 2 years was also significantly higher in the VEPTR group, with 50% versus 13.3% in the MCGR group (P = .0009). As secondary outcomes, radiological parameters such as main curve Cobb angle correction (P = .001) and apical vertebral translation (P = .002) were significantly higher in the MCGR group. Significant differences were also found in sagittal profile parameters; T1-T12 and T1-S1 were significantly higher in the MCGR group (P < .001).

CONCLUSIONS

According to our results, VEPTR has significantly higher complication and reoperation rates at 2 years postsurgery compared with MCGR.

LEVEL OF EVIDENCE

4.

The growth-friendly surgical treatment of scoliosis in children with osteogenesis imperfecta using distraction-based instrumentation

PURPOSE

The study was undertaken to determine the feasibility of growth-friendly distraction-based surgery in children with OI.

METHODS

Two multi-center databases were queried for children with OI who had undergone GR or VEPTR surgery. Inclusion criteria were a minimum 2-year follow-up and three lengthening procedures following the initial implantation. Details of the surgical techniques, surgical complications, and radiographic measurements of deformity correction, T1-T12 and T1-S1 elongation and growth were recorded.

RESULTS

Five patients were identified. There was one patient with type I OI and two patients each with type III and type IV. Four patients had GR constructs and one a VEPTR construct. The initial scoliosis deformity averaged 80° (70°-103°), and the subsequent corrections averaged 32% for initial correction, 48% at last follow-up, and 54% for the two patients that had a final fusion. The T1-T12 and T1-S1 growth averaged 31 mm and 44 mm respectively, and yearly growth averaged 4 mm and 6 mm, respectively. Growth was notably much less in those with more severe disease. There were 13 complications in 4 patients. Nine of the 10 surgical complications were anchor failures which were corrected in 7 planned and 2 un-planned procedures. Significant migration occurred in one patient with severe OI type III.

CONCLUSION

The results varied in this heterogeneous population. In general, satisfactory deformity corrections were obtained and maintained, modest growth was obtained, and complications were similar to those reported in other series of growth-friendly surgery. Limited growth and significant anchor migration are to be anticipated in this population.

LEVEL OF EVIDENCE

IV.

Continuous lengthening potential after four years of magnetically controlled spinal deformity correction in children with spinal muscular atrophy

Magnetically controlled growing rods (MCGR) are commonly implanted for the treatment of early-onset scoliosis. While most authors report favorable short-term results, little is known about long-term deformity correction. This prospective cohort study assesses spinal deformity control in a homogeneous spinal muscular atrophy (SMA) patient group treated with MCGR implants, a standardized lengthening protocol and a minimum follow-up of four years. 17 SMA patients with progressive scoliosis were treated with MCGR implanted parallel to the spine with rib-to-pelvis fixation. Radiologic measurements were performed before and after MCGR implantation and during external lengthening procedures. These included measurements of the scoliotic curve, kyphosis, lordosis, pelvic obliquity and the spinal length. Additional clinical data of the complications were also analyzed. 17 children (mean age 7.4 years) were surgically treated and underwent a total of 376 lengthenings. Complication rates were 3.5% in respect to all interventions or 41% of the patients had complications during 3.5% of the lengthening sessions. The initial implantation significantly reduced the main scoliotic curve by 59%, with the correction remaining constant throughout the follow-up. Pelvic obliquity was also significantly and permanently corrected by 72%, whereas kyphosis and lordosis were not influenced. The spinal length could be significantly increased mostly during the first year of treatment. Bilateral implantation of MCGRs for correction of spinal deformity in children with SMA showed no decrease of the lengthening potential during a four-year follow-up. Therefore, the previously described ‘law of diminishing returns’ could not be applied to this patient population.

Level of Evidence/Clinical relevance: Therapeutic Level IV.

Is rod diameter associated with the rate of rod fracture in patients treated with magnetically controlled growing rods?

INTRODUCTION

Few risk factors for fracture in magnetically controlled growing rods (MCGR) have been identified. We hypothesize an increased rate of rod fracture in small diameter rods compared to large diameter rods in patients with early-onset scoliosis (EOS). The purpose of this study was to determine the association between the diameter of MCGR constructs and the rate of rod fracture.

METHODS

Patients with EOS who underwent MCGR implantation-primary or conversion-from 2013 to 2018 were identified from two registries including 40 centers. Rod diameter sizes greater than 5.0 mm or less than or equal to 5.0 mm were defined as "Large" and "Small" rods, respectively. Only dual-rod constructs were included. The primary outcome measure collected was rod fracture at any point in treatment up to the most recent follow-up. Cox regression was utilized for unequal follow-up to compare rate of breakage at the last follow-up between cohorts.

RESULTS

527 patients with 1,054 rods were included. 552 (52.4%) rods had a diameter of less than or equal to 5.0 mm and 461 (43.7%) rods had a diameter of greater than 5.0 mm. 41 (3.9%) rods were missing a recorded rod diameter and were not included in the analysis to determine the association between the rate of fracture and rod diameter. 20 (1.9%) total rod fractures occurred: 9 (1.6%) rods with diameters of ≤ 5.0 mm, 10 (2.2%) rods with diameters of > 5.0 mm, and 1 uncategorized rod (p = 0.529). No difference in the rate of rod fracture or survival distribution was found between rod diameters of > 5.0 mm and ≤ 5.0 mm even after stratification by ambulatory status, major coronal curve, weight, or location of anchors.

DISCUSSION

Rod fracture appears to be a rare event in dual MCGR constructs and rod diameter does not seem to be associated with the incidence or rate of rod fracture. Surgeons may consider other criteria for selecting rod diameter in their patients such as patient size, amount of surgical correction, single vs. dual constructs, and risk of hardware prominence.

The Association Between the Utilization of Traction and Postoperative Complications Following Growing Rod Instrumentation for Early-onset Scoliosis

BACKGROUND

Preoperative and/or intraoperative traction have been proposed as adjunctive methods to limit complications associated with growth-friendly instrumentation for early-onset scoliosis (EOS). By gradually correcting the deformity before instrumentation, traction can, theoretically, allow for better overall correction without the complications associated with the immediate intraoperative correction. The purpose of this multicenter study was to investigate the association between preoperative/intraoperative traction and complications following growth-friendly instrumentation for EOS.

METHODS

Patients with EOS who underwent growth rod instrumentation before 2017 were identified from 2 registries. Patients were divided into 2 groups: preoperative traction group versus no preoperative traction group. A subgroup analysis was done to compare intraoperative traction only versus no traction. Data was collected on any postoperative complication from implantation to up to 2 years postimplantation.

RESULTS

Of 381 patients identified, 57 (15%) and 69 (18%) patients received preoperative and intraoperative traction, respectively. After adjusting for etiology and degree of kyphosis, there was no evidence to suggest that preoperative halo traction reduced the risk of any complication following surgical intervention. Although not statistically significant, a subgroup analysis of patients with severe curves demonstrated a trend toward a markedly reduced hardware failure rate in patients undergoing preoperative halo traction [preoperative traction: 1 (3.1%) vs. no preoperative traction: 11 (14.7%), P=0.083]. Nonidiopathic, hyperkyphotic patients treated with intraoperative traction were 61% less likely to experience any postoperative complication (P=0.067) and were 74% (P=0.091) less likely to experience an unplanned return to the operating room when compared with patients treated without traction.

CONCLUSIONS

This multicenter study with a large sample size provides the best evidence to date of the association between the use of traction and postoperative complications. Our results justify the need for future Level I studies aimed at characterizing the complete benefit and risk profile for the use of traction in surgical intervention for EOS.

LEVEL OF EVIDENCE

Level III.

VEPTR Treatment of Early Onset Scoliosis in Children Without Rib Abnormalities: Long-term Results of a Prospective, Multicenter Study

BACKGROUND

In 2007, this prospective study on vertical expandable prosthetic titanium rib (VEPTR) treatment of early onset scoliosis in children without rib abnormalities was initiated. Two-year follow-up results have previously been reported. This study examines whether, at 5-year follow-up, VEPTR continues to control scoliosis and allow spinal growth.

METHODS

A prospective, multicenter, observational cohort design was used. Patients underwent traditional VEPTR implantation ≥5 years before analysis. Preimplantation and last available images were compared, regardless of whether VEPTR remained in vivo. Additional analysis was performed if VEPTR was in vivo ≥5 years.

RESULTS

This study included 59 patients (mean age at VEPTR implantation, 6.1±2.4 y; mean follow-up, 6.9±1.4 y). Currently, 24 patients still have VEPTR, whereas 24 have converted (13 fusions, 6 MCGR, 3 growing rods, 1 hybrid, and 1 Shilla). Three have had VEPTR explanted, 6 are unknown, and 2 have deceased. On last available imaging (n=59; mean follow-up, 4.8±1.9 y), scoliosis improved from 71.8±18.0 degrees preoperatively to 60.9±20.3 degrees (P<0.001) and T1- T12 height increased (15.8±3.2 to 19.3±3.8 cm, P<0.001). T1-S1 height also increased (24.8±4.4 to 31.2±5.3 cm, P<0.001), representing 119% age-matched growth. Composite improvement of scoliosis, T1-T12, and T1-S1 height was achieved in 79% of patients. A subset of 29 patients with VEPTR was analyzed at most recent follow-up ≥5 years while VEPTR remained in vivo (24 patients with VEPTR above, and 5 who later converted to other devices). Mean age at implantation was 5.0±2.2 years, with a mean VEPTR treatment duration of 6.2±1.1 years. Scoliosis improved from preoperatively (69.3±14.5 to 61.6±16.1 degrees, P=0.006), with mild recurrence from postoperative to 5 years. T1-T12 height increased (15.0±3.3 to 18.7±3.3 cm, P<0.001) and T1-S1 height increased (23.7±4.5 to 30.1±4.6 cm, P<0.001), representing 83% age-matched growth. Composite improvement was achieved in 83% of patients. Instrumented sagittal length also increased during this period (21.8±4.2 to 30.3±5.1 cm, P<0.001).

CONCLUSION

At a 5-year follow-up, VEPTR continues to control scoliosis and allow spinal growth.

LEVEL OF EVIDENCE

Level II-prospective cohort, therapeutic study.

Unplanned return to operation room (OR) following growing spinal constructs (GSCs) in early onset scoliosis (EOS)-a multi-centric study

PURPOSE

To evaluate the incidence and risk factors associated with the unplanned return to OR in EOS.

METHODS

Medical records of 51 patients of EOS operated at three different centres using various types of GSCs were evaluated for complications requiring unplanned surgeries. Data were analysed to find out rate of unplanned surgeries in relation to the aetiology, age and Cobb angle at index surgery, type of implant, cause of unplanned surgery, and management required.

RESULTS

Out of 51 patients, three did not meet inclusion criteria. Forty-eight patients of EOS operated by GSCs with a mean age of 6.7 years (range 2-12 years) with an average follow-up of 67.3 months were studied. There were 30 congenital, 10 idiopathic, 4 syndromic, and 4 neuromuscular cases. Thirty-nine out of 48 patients had one or more unplanned surgeries on follow-up (81.25%). Out of total 248 surgeries following index procedure, 82 were unplanned surgeries (33.06%), including 53 implant revisions, 12 implant-removal, 14 debridement, and 2 flaps. The common complications were 24.14% rod/screw breakage, 42.53% anchor pull-out, 16.09% infections, 6.90% wound dehiscence, and 4.6% neuro deficits. Unplanned surgeries were significantly higher in syndromic (58.8%) and neuromuscular (52.9%) than congenital (27.2%) and idiopathic (37.8%) cases (p < 0.05). Age at index procedure < 5 years had higher unplanned surgeries than age > 5 years (2.5 and 1.23 per patient, respectively,  p < 0.05). Type of implant and initial Cobb angle did not significantly affect the rate of unplanned surgeries (p  > 0.05) CONCLUSION: GSCs in EOS require a frequent revisit to operation room which should be well understood by the surgeon and parents.

Radiographic Outcome and Complication Rate of 34 Graduates After Treatment With Vertical Expandable Prosthetic Titanium Rib (VEPTR): A Single Center Report

BACKGROUND

The final strategy for graduates from growth-sparing surgery is challenging. The purpose of this study was to evaluate the radiographic outcome and complications of patients with early onset scoliosis (EOS) who have graduated from vertical expandable prosthetic titanium rib (VEPTR) treatment, either undergoing final fusion surgery or following a nonfusion approach.

METHODS

Final treatment for VEPTR graduates was divided in "VEPTR in situ without final fusion," "removal of VEPTR without final fusion," and "removal of VEPTR with instrumented final fusion." Radiographic evaluations included main coronal Cobb angle and main kyphosis pre and post VEPTR implantation, at the end of implant lengthening, after final fusion (if applicable), and at latest follow-up. Complications during VEPTR treatment and in case of final fusion were reported.

RESULTS

In total, 34 VEPTR graduates were included; 17 underwent final fusion surgery, and 17 followed a nonfusion strategy. Average coronal Cobb angle before VEPTR implantation was 70±23 degrees (range, 21 to 121 degrees), and 65±22 degrees (range, 17 to 119 degrees) at latest follow-up. Average main kyphosis angle was 53±27 degrees (range, 6 to 137 degrees) before VEPTR, and 69±34 degrees (range, 10 to 150 degrees) at latest follow-up. There was a 41% complication rate with final fusion surgery.

CONCLUSIONS

There is a high complication rate during VEPTR treatment and with final fusion surgery. The stiffness of the spine and thorax allow for only limited correction when performing a final instrumented spondylodesis. Avoiding final fusion may be a viable alternative in case of good coronal and sagittal alignment.

LEVEL OF EVIDENCE

Level IV-therapeutic.

A novel growing rod technique to treat early-onset scoliosis (EOS): a step-by-step 2D surgical video

Early-onset scoliosis (EOS) correction techniques have evolved slowly over the past 40 years and still remain a challenge for the spine surgeon. Avoiding spinal fusion in these patients is key to decreasing morbidity and mortality in this population.

Current treatments for EOS include both conservative and surgical options. The authors present the modified Luqué technique that has been performed at their institution for the past decade. This modified technique relies on Luqué’s principle, but with newer “gliding” implants through a less disruptive approach. The goal of this technique is to delay fusion as long as possible, with the intent to prevent deformity progression while preserving maximal growth.

Normally, these patients will have definitive fusion surgery once they have reached skeletal maturity or as close as possible. Out of 23 patients until present (close to 4-year follow-up), the authors have not performed any revision due to implant failure. Three patients have undergone final fusion as the curve progressed (one patient, 4 years out, had final fusion at age 12 years; two other patients had final fusion at 3 years). These implants, which have the CE mark in Europe, are available in Canada via a special access process with Health Canada. The implants have not yet been submitted to the FDA, as they are waiting on clinical data out of Europe and Canada.

In the following video the authors describe the modified Luqué technique step-by-step.

The video can be found here: https://youtu.be/k0AuFa9lYXY.

Long term outcome of vertical expandable prosthetic titanium rib treatment in children with early onset scoliosis

The vertical expandable prosthetic titanium rib (VEPTR) device was originally developed for the treatment of thoracic insufficiency syndrome with the aim of improving respiratory function of affected patients. Although clinically obvious, the changes in pulmonary function of VEPTR-treated patients are difficult to assess when using common lung function tests, and newer techniques based on functional magnetic resonance imaging (MRI) are currently being evaluated. The potential of improving lung function and simultaneously controlling the spinal deformity has continuously broadened the spectrum of indications for VEPTR, not least due to the frequent reports of complications with spine-based traditional growing rods (tGR). However, the initial enthusiasm of spine-sparing deformity correction has progressively subsided with the increasing number of reports on complications, including the detection of extraspinal ossifications along the implants and across ribs. The avoidance of repetitive surgical implant lengthening with the availability of motorized distraction-based implants has further diminished the use of VEPTR, especially in the absence of volume-depletion deformities of the thorax. In view of the still scarce reporting on the ultimate strategy of VEPTR treatment and the lack of long-term follow-up of patients receiving growth-sparing surgery, only limited conclusions can be drawn so far. Based on the available reports, however, the intended deformity corrections with final fusion surgeries can be achieved to a rather limited extent, while the complication and reoperation rates are still very high.

The Effect of Expansion Thoracostomy on Spine Growth in Patients with Spinal Deformity and Fused Ribs Treated with Rib-Based Growing Constructs

STUDY DESIGN

Retrospective review of prospective registries.

OBJECTIVES

We hypothesized that patients with congenitally fused ribs who underwent thoracostomy upon implantation of rib-based distraction devices would achieve improved spine growth compared with those who did not undergo thoracostomy.

SUMMARY OF BACKGROUND DATA

Patients with fused ribs may develop thoracic insufficiency syndrome. Treatment for severe early-onset spinal deformity with rib fusions often includes the placement of rib-based expansion devices with surgical division of the fused ribs (thoracostomy). The effect of thoracostomy on spinal growth has not been fully examined.

METHODS

Two multicenter registries of primarily prospectively collected data were searched. Patients with fused ribs and implantation of a rib-based device were identified. A total of 151 patients with rib fusions treated with rib-based constructs and minimum two-year follow-up were included. Among those, 103 patients were treated with expansion thoracostomy at the time of implantation, whereas 48 patients received device implantation alone. We evaluated change in T1-T12 and T1-S1 height, coronal Cobb angle, kyphosis, and number of surgeries. Preoperative deformity was similar between the two groups. Only 19% of patient underwent final fusion, with similar numbers fused in each group.

RESULTS

At latest follow-up, the expansion thoracostomy group had a greater total improvement in T1-S1 height (7.2 cm vs. 4.8 cm, p = .004). There was no difference between the two groups for change in spinal height at each lengthening procedure. Interestingly, thoracostomy patients also underwent more total surgeries (11.5 vs. 9.6, p = .031) and more lengthening procedures (8.3 vs. 6.6, p = .017) than the comparison group despite similar length of follow-up.

CONCLUSIONS

Patients who underwent expansion thoracostomy at the time of rib expansion device implantation achieved greater improvement in T1-S1 height than those who underwent implantation of rib expansion device alone. Further work is needed to evaluate whether expansion thoracostomy impacts pulmonary function.

Growth-Friendly Spine Surgery in Escobar Syndrome

BACKGROUND

The aims of this study were to characterize the spinal deformity of patients with Escobar syndrome, describe results of growth-friendly treatments, and compare these results with those of an idiopathic early-onset scoliosis (EOS) cohort to determine whether the axial stiffness in Escobar syndrome limited correction.

METHODS

We used 2 multicenter databases to review the records of 8 patients with EOS associated with Escobar syndrome who had at least 2-year follow-up after initiation of growth-friendly treatment from 1990 to 2016. An idiopathic EOS cohort of 16 patients matched for age at surgery (±1 y), postoperative follow-up (±1 y), and initial curve magnitude (±10 degrees) was identified. A randomized 1:2 matching algorithm was applied (α=0.05).

RESULTS

In the Escobar group, spinal deformity involved 7 to 13 vertebrae and ranged from no vertebral anomalies in 3 patients to multiple segmentation defects in 6 patients. Mean age at first surgery was 5 years (range, 1.4 to 7.8 y) with a mean follow-up of 7.5 years (range, 4.0 to 10 y). Mean major curve improved from 76 degrees at initial presentation, to 43 degrees at first instrumentation, to 37 degrees at final follow-up (both P<0.001). Mean pelvic obliquity improved from 16 degrees (range, 5 to 31 degrees) preoperatively to 4 degrees (range, 0 to 8 degrees) at final follow-up (P=0.005). There were no differences in the mean percentage of major curve correction between the idiopathic EOS and Escobar groups at the immediate postoperative visit (P=0.743) or final follow-up (P=0.511). There were no differences between the cohorts in T1-S1 height at initial presentation (P=0.129) or in growth per month (P=0.211).

CONCLUSIONS

Multiple congenital fusions and spinal curve deformity are common in Escobar syndrome. Despite large areas of congenital fusion, growth-friendly constructs facilitate spinal growth and improve curve correction. These results are comparable to those in idiopathic EOS.

LEVEL OF EVIDENCE

Level III-case-control study.

[Surgical "no-touch" distraction technique to correct pediatric scoliosis]

OBJECTIVE

Reduction and retention of the scoliotic curve in children with progressive spinal deformities.

INDICATIONS

Progressive neuromyopathic scoliosis which cannot be controlled conservatively (especially by walking disability), and/or development of a thorax insufficiency syndrome (TIS).

CONTRAINDICATIONS

Insufficient soft tissue coverage; body weight < 11.4 kg; body mass index (BMI) > 25 or >50 kg; missing osseous anchoring structures (ribs); adult skeleton (usually age < 12 years at surgery); severe spasticity.

SURGICAL TECHNIQUE

Indirect correction and distraction of the spinal deformity by two extendable, paravertebral telescopic implants, anchored to the cranial ribs and the iliac crest; the spine is not compromised surgically.

POSTOPERATIVE MANAGEMENT

Early functional therapy, no brace; multiple surgical (VEPTR®-system) or externally (magnetically controlled rods) controlled extensions per year.

RESULTS

The surgical paravertebral "no-touch" technique for spine correction is particularly suitable for children with neuromyopathic scoliosis with a body weight > 11.4 kg. Our prospective group of children (n = 45), was treated with a combination of the classic vertical expandable prosthetic titanium rib (VEPTR®) anchored to the ribs and iliac crest combined with a magnetically controlled telescopic implant (MAGEC®). The primary correction of >50% was achieved, while progression was effectively prevented over years. In 495 outpatient lengthening procedures, the rate of implant-associated complications requiring surgery was 3.7%. Of the 45 children, 13 (29%) underwent surgical revision. With the proposed surgical "no-touch" technique for scoliosis correction of pediatric neuromyopathic deformities, an effective reduction of the scoliotic curve can be achieved and maintained. Advantages of the method are a partial retention of spinal flexibility and a reduction of spinal ossifications, which facilitates dorsal spondylodesis as the final treatment.

Treatment of early onset spinal deformities with magnetically controlled growing rods: a single centre experience of 30 cases

PURPOSE

The treatment of early onset scoliosis continues to be a major challenge, even when using motorized growth-sparing implants. We report on 30 cases operated on with magnetically controlled growing rods (MCGRs) at our institution, analyzing radiological parameters and complications, comparing our results with the literature and presenting a special implant fixation technique. A separate focus highlights the challenges of conversion from previous non-motorized implants.

METHODS

Consecutive case series. The nature and effects of complications were recorded for all patients. Radiographic evaluations were performed for patients with a minimum follow-up of two years. Separate analyses were carried out for patients who were previously treated with non-motorized growth-sparing implants.

RESULTS

There were 12 documented complications in 11/30 (37%) patients leading to 13 unplanned returns to the operating room. In all, 18/30 patients had a minimum follow-up of two years. Major curve and main kyphosis, as well as T1 to T12 and T1 to S1 distances significantly improved with MCGR implantation, however, less in patients converted from previous growth-sparing surgical treatment. While the achieved correction of the major curve was maintained, there was a loss of kyphosis correction with subsequent implant lengthening. Gain in implant length decreased with increasing number of extensions.

CONCLUSION

Despite improved patient's comfort, MCGR show a considerable complication rate. Coronal plane deformities can be well controlled, but diminished implant lengthening is already apparent within two years after MCGR implantation. Central databases should help to clarify unresolved aspects and optimize the treatment of these young patients.

LEVEL OF EVIDENCE

IV.

Long-term Outcome of Early Fusions for Congenital Scoliosis

STUDY DESIGN

The current literature on outcomes of early fusions for early-onset scoliosis (EOS) has a short follow-up of 7.7 to 12.5 years, with many patients not at the end of growth. The forced vital capacity (FVC) at follow-up ranged from 40.8% to 64% of predicted. A study was undertaken to evaluate the long-term outcome of these fusions.

METHODS

The study is of congenital patients who had a fusion under age 8 years, with the current age being >20 years. A follow-up consisting of radiographs, outcome questionnaires, and pulmonary function tests was performed. Of the 42 patients identified, 20 were traced and 11 agreed to participate, and completed all the data. The average follow-up was 37 years. All the fusions included the thoracic spine, with an average of 10.2 levels fused, of which an average of 8.8 levels were thoracic.

RESULTS

The average scoliosis at presentation was 52°, 56° at surgery and 47° at follow-up. At follow-up, the average FVC was 53% of predicted, with an average PaO₂ of 86 and PaCO₂ of 44 mm Hg. The mean T1-T12 length was 20 cm. There was no correlation of the FVC percentage predicted and the proximal extent of the fusion, the T1-T12 length or the number of thoracic levels fused. The average ODI was 23. On the SF36, the average Physical Component t score was 50; with the average Mental Component t score was 52.

CONCLUSION

At a long-term average follow-up of 37 years, the patients had a low FVC of 53%, with one on permanent oxygen and 5 with dyspnea. The patients were functioning well at follow-up, but it is unknown what their function would be without surgery or with longer follow-up.

Parallel Proximal Fixation in Rib-Based Growing Rod System: A Novel Approach to Deal With Proximal Anchor Migration

STUDY DESIGN

Retrospective case control.

OBJECTIVE

To report on differences in implant failure rates and complications requiring reoperation in children with early-onset scoliosis (EOS) treated with rib-based distraction utilizing four proximal fixation points in either a parallel or in-line configuration.

SUMMARY OF BACKGROUND DATA

Proximal anchor failure continues to be a significant problem in growth-friendly surgery using rib-based distraction to treat children with EOS. Differences between parallel and in-line proximal anchor constructs have not been previously assessed.

METHODS

A multicenter registry was reviewed to identify children treated for EOS with rib-based distraction between 2011 and 2014 with a minimum of 2 years follow-up after implantation. Patients were divided into those with in-line and parallel proximal rib-cradle configurations, and only those with exactly four fixation points (two per side) were included. Charts were reviewed for demographic, clinical, and radiographic information.

RESULTS

A total of 56 patients were identified-31 with in-line constructs and 25 with parallel constructs. Follow-up in the in-line group was a mean of 4.06 years versus 3.16 in the parallel group (P = 0.001). Controlling for the different lengths of follow-up in the two groups there was a significantly higher rate of implant failure (P = 0.043) and requirement for nonroutine surgical intervention (P = 0.029) in the in-line group. There was a trend toward increased complications in the in-line group (P = 0.058).

CONCLUSION

Failure of proximal fixation is the most common complication in management of EOS with rib-based distraction. This study identifies that when the number of proximal fixation points are matched, parallel constructs result in lower rates of implant failure and need for unplanned reoperation than in-line constructs. Although this study was limited to patients in whom the VEPTR device was employed, these principles are likely applicable to other rib-based distraction devices used to treat EOS.

LEVEL OF EVIDENCE

3.

Combining Bilateral Magnetically Controlled Implants Inserted Parallel to the Spine With Rib to Pelvis Fixation: Surgical Technique and Early Results

Spine-based fixation of magnetically controlled lengthening devices has been successfully performed for children with early-onset scoliosis. However, spinal manipulation may lead to ossifications, stiffness, and autofusion as previously described. To avoid these problems, a surgical technique combining bilateral externally controlled magnetic device implantation with a rib cradle and pelvic hook fixation was introduced by us in 2011. By using a bilateral single-rib or double-rib cradle fixation and a pelvic hook, the magnetic device is percutaneously inserted. The spine corrects indirectly without further manipulation. In small rib diameter or severe osteoporosis, double-rib cradles are used. Our introduced technique enables modification of the rib vertebral angle, which may be beneficial in children with spinal muscular atrophy and rib-cage deformity. This nonrandomized prospective study describes 18 children with neuromuscular scoliosis treated first by this method. All patients followed the same protocol, with expansion procedures being performed 5 months after surgery and every 3 months thereafter. Clinical, radiologic, and complication data were analyzed, showing a significant reduction in scoliosis and pelvic obliquity and an increase in spinal length, which could be maintained over a follow-up period of 1.2 years. The overall complication rate was lower than previously described, with 8%, 2 of them requiring surgery.

Early-onset Scoliosis: Contemporary Decision-making and Treatment Options

Early-onset scoliosis (EOS) describes a wide array of diagnoses and deformities exposed to growth. This potentially life-threatening condition is still 1 of the biggest challenges in pediatric orthopaedics. The enlightenment of Bob Campbell's thoracic insufficiency syndrome concept and the negative impact of the earlier short and straight spine fusion approach on respiratory function and survival have fueled the evolution of EOS care. Despite all the progress made, growth-friendly spine surgery remains to be a burden to patients and caregivers. Even down-sized implants and remote-controlled noninvasive rod expansions do not omit unexpected returns to the operating room: failures of foundations, rod breakage, difficulties to keep the sagittal balance, progressive transverse plane deformities, stiffening, and the need for final instrumented fusion are still common. However, past experience and the current multitude of surgical strategies and implants have sharpened the decision-making process, patients with thoracic insufficiency syndrome require earliest possible vertical expandable prosthetic titanium ribs application. Flexible deformities below 60 degrees, with normal spinal anatomy and without thoracic involvement, benefit from serial Mehta casting which revived as a long available but not-used strategy. In case of progression, standard double growing rods or-if available, affordable, and applicable-magnetically controlled motorized rods provide deformity control and growth promotion. Shilla growth-guiding technique is a less costly alternative. Its lack of stiff lengthening boxes or actuators may be beneficial in difficult deformities. Anterior convex flexible tethering promises benefits of sparing the trunk muscles and keeping mobility. However, this step towards a true nonfusion concept has yet to stand the test of broad clinical application.

Ligament augmentation for prevention of proximal junctional kyphosis and proximal junctional failure in adult spinal deformity

OBJECTIVE Proximal junctional kyphosis (PJK) is a well-recognized, yet incompletely defined, complication of adult spinal deformity surgery. There is no standardized definition for PJK, but most studies describe PJK as an increase in the proximal junctional angle (PJA) of greater than 10°-20°. Ligament augmentation is a novel strategy for PJK reduction that provides strength to the upper instrumented vertebra (UIV) and adjacent segments while also reducing junctional stress at those levels. METHODS In this study, ligament augmentation was used in a consecutive series of adult spinal deformity patients at a single institution. Patient demographics, including age; sex; indication for surgery; revision surgery; surgical approach; and use of 3-column osteotomies, vertebroplasty, or hook fixation at the UIV, were collected. The PJA was measured preoperatively and at last follow-up using 36-inch radiographs. Data on change in PJA and need for revision surgery were collected. Univariate and multivariate analyses were performed to identify factors associated with change in PJA and proximal junctional failure (PJF), defined as PJK requiring surgical correction. RESULTS A total of 200 consecutive patients were included: 100 patients before implementation of ligament augmentation and 100 patients after implementation of this technique. The mean age of the ligament augmentation cohort was 66 years, and 67% of patients were women. Over half of these cases (51%) were revision surgeries, with 38% involving a combined anterior or lateral and posterior approach. The mean change in PJA was 6° in the ligament augmentation group compared with 14° in the control group (p < 0.001). Eighty-four patients had a change in PJA of less than 10°. In a multivariate linear regression model, age (p = 0.016), use of hook fixation at the UIV (p = 0.045), and use of ligament augmentation (p < 0.001) were associated with a change in PJA. In a separate model, only ligament augmentation (OR 0.193, p = 0.012) showed a significant association with PJF. CONCLUSIONS Ligament augmentation represents a novel technique for the prevention of PJK and PJF. Compared with a well-matched historical cohort, ligament augmentation is associated with a significant decrease in PJK and PJF. These data support the implementation of ligament augmentation in surgery for adult spinal deformity, particularly in patients with a high risk of developing PJK and PJF.

Spinal deformity changes in children with long-term vertical expandable prosthetic titanium rib treatment

BACKGROUND CONTEXT

In several studies, vertical expandable prosthetic titanium rib (VEPTR) implants have shown good scoliosis control in children with the longest reported follow-up of 3.6 years. For growing rods, recent studies suggest a decreased efficiency of correction starting just after that time. To our knowledge, no long-term results of children with VEPTR treatment are available.

PURPOSE

This study aimed to evaluate spinal deformity in scoliotic children and to investigate correction potential of VEPTR implants at several time points of treatment, particularly after long-term follow-up.

STUDY DESIGN/SETTING

We performed a retrospective case series of 32 children with spinal deformity and VEPTR treatment with analysis of clinical and radiological data pre- and post-VEPTR implantation and every 2 years during the follow-up period.

PATIENT SAMPLE

Thirty-two patients with spinal deformity and VEPTR treatment comprised the patient sample.

OUTCOME MEASURES

Patients had a primary VEPTR implantation due to spinal deformity and thoracic insufficiency syndrome and repeated lengthening procedures every 6 months. Clinical data were assessed and radiological parameters were analyzed. The main thoracic scoliotic curve and associated curves as well as kyphosis, lordosis, pelvic obliquity, and spinal length were measured in all radiographs until the end of VEPTR treatment or the last available examination.

METHODS

Development of the different parameters during follow-up was evaluated and statistical analysis was performed with Statistica version 13.0. No funding was obtained for this study. The authors have no conflicts of interest to declare.

RESULTS

Directly after VEPTR implantation, thoracic and lumbar curves corrected significantly, were stable at 2.8-year follow-up, and increased at 5.5-year follow-up, whereas cervical scoliosis was not affected by the treatment. The sagittal profile was initially improved both in kyphosis and lordosis. However, at 5.5-year follow-up, hyperkyphosis had deteriorated beyond the initial deformity. Pelvic obliquity was significantly restored especially in neuromuscular patients, and increasing spinal length was achieved within the 5.5-year follow-up.

CONCLUSION

In children with spinal deformity, implantation of the VEPTR device sufficiently corrected the deformity in all planes. During long-term follow-up, scoliosis increased slightly and was rather well controlled, whereas the implant system was not able to prevent deterioration of hyperkyphosis. Pelvic obliquity was well balanced and spinal lengthening was achieved during long-term follow-up.

Use of a Vertical Expandable Prosthetic Titanium Rib in Children With Thoracic Insufficiency Syndrome and Scoliosis

Thoracic insufficiency syndrome is the inability of the thorax to support normal respiration or lung growth. One treatment to address the thoracic deformities associated with the syndrome is placement of a vertical expandable prosthetic titanium rib. The goal is to restore thoracic volume, symmetry, and function and to allow for growth of the thorax in skeletally immature children. The main topics include indications for placement of a titanium rib, postoperative nursing care, potential complications, long-term follow-up, quality-of-life issues, and implications for critical care nurses and advanced practice nurses.

VEPTR Implantation to Treat Children With Early-Onset Scoliosis Without Rib Abnormalities: Early Results From a Prospective Multicenter Study

BACKGROUND

Thoracoplasty and insertion of vertical expandable prosthetic titanium rib (VEPTR) for thoracic and spine distraction has been found to be effective in the treatment of early-onset scoliosis (EOS) with ribs anomalies and congenital vertebral anomalies. The aim of this study was to evaluate the efficacy of VEPTR in preventing further progression of scoliosis without impeding spinal growth in children with progressive EOS without rib abnormalities.

METHODS

This is a prospective, multicenter, observational cohort study. Erect radiographs were analyzed for coronal and sagittal curve and height measurements at preimplant, immediate postoperative, and at 2-year follow-up.

RESULTS

Sixty-three patients met inclusion: 35 males and 28 females. Mean age at time of implantation was 6.1±2.4 years. Etiologies included congenital (n=6), neuromuscular (n=36), syndromic (n=4), and idiopathic (n=17). The mean follow-up was 2.2±0.4 years. Scoliosis (72±18 degrees) decreased after implant surgery (47±17 degrees) followed by slight increase at 2-year follow-up (57±18 degrees), P<0.0001. Kyphosis (48±22 degrees) also showed significant decrease after implantation (40±14 degrees), but increased after 2 years (48±16 degrees), P<0.0001. Coronal spine height measurements including T1-T12 (15.7±3 cm) and T1-S1 (25±6 cm) showed significant increases after implantation surgery (17.7±4 cm and 28.6±6 cm, respectively) and at 2 years (18.4±4 cm and 29.1±5 cm, respectively), P<0.0001. The increase in coronal spine height represented 144% of expected age-matched T1-T12 growth and 193% of expected age-matched T1-S1 growth. Similarly, sagittal spine length of T1-T12 and T1-S1 increased from 16.9±2.7 cm and 27.1±3.9 cm, respectively preoperatively to 19.7±3.5 cm and 31.9±5.1 cm, respectively at 2-year follow-up, P<0.0001. The instrumented spine segment continued growth from 25.8±5.2 cm after implantation to 27.4±5.3 cm at 2-year follow-up, P<0.0001. Thirty-one patients (49%) had at least 1 complication with total of 58 complications.

CONCLUSIONS

At 2-year follow-up, VEPTR was effective in treating EOS without rib abnormalities with 86% of patients having an improvement in scoliosis and 94% of patients having an increased spinal height as compared with preoperative values. This study proved that spine continues to grow after VEPTR instrumentation during the distraction phase. This amount of growth represents about 40% for T1-T12 and 31% for T1-S1 spine of the expected age-matched growth based on Dimeglio reference numbers. We find this growth important as it proves continuous spine growth with VEPTR treatment.

LEVEL OF EVIDENCE

Level II.

Evolution of the postoperative sagittal spinal profile in early-onset scoliosis: is there a difference between rib-based and spine-based growth-friendly instrumentation?

OBJECTIVE Although the vertical expandable prosthetic titanium rib (VEPTR) and growing rod instrumentation (GRI) encourage spinal growth via regular lengthening, they can create different results because of their different fixation patterns and mechanisms in correcting scoliosis. Previous studies have focused comparisons on coronal plane deformity with minimal attention to the sagittal profile. In this retrospective study, the authors aimed to compare the evolution of the sagittal spinal profile in early-onset scoliosis (EOS) treated with VEPTR versus GRI. METHODS The data for 11 patients with VEPTR and 22 with GRI were reviewed. All patients had more than 2 years' follow-up with more than 2 lengthening procedures. Radiographic measurements were performed before and after the index surgery and at the latest follow-up. The complications in both groups were recorded. RESULTS Patients in both groups had similar diagnoses, age at the index surgery, and number of lengthening procedures. The changes in the major coronal Cobb angle and T1-S1 spinal height were not significantly different between the 2 groups. Compared with the GRI group, the VEPTR group had less correction in thoracic kyphosis (23% ± 12% vs 44% ± 16%, p < 0.001) after the index surgery and experienced a greater correction loss in thoracic kyphosis (46% ± 18% vs 11% ± 8%, p < 0.001) at the latest follow-up. Although the increase in the proximal junctional angle was not significantly different (VEPTR: 7° ± 4° vs GRI: 8° ± 5°, p = 0.569), the incidence of proximal junctional kyphosis was relatively lower in the VEPTR group (VEPTR: 18.2% vs GRI: 22.7%). No significant changes in the spinopelvic parameters were observed, while the sagittal vertical axis showed a tendency toward a neutral position in both groups. The overall complication rate was higher in the VEPTR group than in the GRI group (72.7% vs 54.5%). CONCLUSIONS The VEPTR had coronal correction and spinal growth results similar to those with GRI. In the sagittal plane, however, the VEPTR was not comparable to the GRI in controlling thoracic kyphosis. Thus, for hyperkyphotic EOS patients, GRI is recommended over VEPTR.

Detection of Bacteria Colonizing Titanium Spinal Implants in Children

BACKGROUND

Bacterial colonization of spinal implants may cause severe complications in patients with early-onset scoliosis. Correct diagnosis and detection of microbiologic formation is crucial to prevent delayed infections caused by bacterial colonization. The purposes of this study were to estimate the rate and risk factors of colonization of vertical expandable prosthetic titanium rib (VEPTR) implants in children and to compare the different methods for detecting microbiologic formation on the spinal implants.

METHODS

We evaluated prospectively a group of 42 children with spinal deformities with an overall of 95 lengthening surgeries and applied different methods to detect potential bacterial colonization of VEPTR implants: swab of the implant, swab with culture of tissue, analysis of the removed lock, polymerase chain reaction (PCR), and confocal microscopy. Potential risk factors were evaluated.

RESULTS

Of 42 patients, 17 (40%) were rated positive for bacterial colonization with Propionibacterium acnes and coagulase-negative staphylococci being the most commonly found bacteria. Risk factors for colonization were increasing age, body height, and weight. The swab with culture of removed tissue yielded most positive results, whereas direct microscopy and PCR were the least sensitive detection methods. Furthermore, commonly used infectious blood parameters were inconclusive.

CONCLUSIONS

Although the impact of bacterial colonized implants on the health of the patients is not fully elucidated, clinicians aim for prevention of microbiologic formation on implanted devices. Therefore, reliable, inexpensive, and easy to apply diagnostic tools are indispensable to detect colonization. Based on our data, the swab together with tissue culture has the potential to become the method of choice for future diagnosis.

Magnetically Controlled Devices Parallel to the Spine in Children with Spinal Muscular Atrophy

Background:

Children with severe spinal deformity frequently are managed with growth-friendly implants. After initial surgery, externally controlled magnetic rods allow spinal deformity correction during growth without further surgical intervention. The ability to lengthen the spine without additional surgical procedures is especially beneficial in high-risk children, such as those with spinal muscular atrophy (SMA). The purpose of the present study was to assess the level of control of spinal deformity in a homogeneous group of patients with SMA who were managed with magnetically controlled implants for 2 years.

Methods:

This prospective, nonrandomized study included 21 non-ambulatory children with type-II SMA and progressive scoliosis who were managed bilaterally with a magnetically controlled implant that was inserted parallel to the spine with use of rib-to-pelvis hook fixation. Radiographic measurements of scoliotic curves, kyphosis, lordosis, pelvic obliquity, and spinal length were performed before and after implantation of the magnetically controlled device and during external lengthening. The mean duration of follow-up was 2 years.

Results:

The mean main curve of patients without prior vertical expandable prosthetic titanium rib (VEPTR) treatment decreased from 70° before implantation of the magnetically controlled device to 30° after implantation of the device. Correction was maintained during the follow-up period, with a mean curve of 31° at the time of the latest follow-up at 2.2 years. Pelvic obliquity was surgically corrected by 76% (from 17° to 4°) and remained stable during follow-up. Thoracic kyphosis could not be corrected within the follow-up period. Spinal length of children without prior spinal surgery increased by >50 mm immediately after device implantation and steadily increased at a rate of 13.5 mm/yr over the course of treatment. During treatment, 4 general complications occurred and 6 lengthening procedures failed, with 3 patients requiring surgical revision.

Conclusions:

Bilateral implantation of an externally controlled magnetic rod with rib-to-pelvis fixation represents a safe and efficient method to control spinal deformity in children with SMA, achieving sufficient and stable curve correction as well as increased spinal length. The complication rate was lower than those that have been described for VEPTR and other growing rod instrumentation strategies.

Level of Evidence:

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Evaluation of the Modern Luque Trolley Construct for the Treatment of Early-onset Scoliosis Using a Gliding Implant in an Immature Animal Model

STUDY DESIGN

This was an experimental animal study.

OBJECTIVE

To determine biological compatibility, stability, and growth potential of the Trolley Gliding Vehicle (TGV) used in a novel surgical technique for guided spinal growth.

SUMMARY OF BACKGROUND DATA

Current treatments for early-onset scoliosis maintaining spinal growth consist of posteriorly based spinal constructs requiring repetitive lengthening. Such interventions have a high rate of complications. Using a muscle-sparing technique, a modified dual-growing rods construct, and new sliding spinal anchors, we aimed to test a modern Luque Trolley construct in an immature animal model.

MATERIALS AND METHODS

Six matched pairs of 3-month-old lambs were randomized to an observation or a surgical group and were followed for 9 months. The surgical group was subjected to implantation of a modern Luque Trolley construct with the new TGV inserted using a minimally invasive transmuscular technique capturing the spine and the 2 overlapping rods on either side. Physical examinations and imaging were performed at routine intervals, with a subsequent necropsy.

RESULTS

The spines of the study group grew 96% between the instrumented segments compared with the control group without evidence of implant failure. In total, 42% of the fixed anchors (pedicle screws) and 13.90% of the TGV were loose. All 6 animals had some heterotrophic bone formation tracking along the rods (<20%) mainly originating from the distal anchor point. We identified 19 unplanned spontaneous facet arthrodesis out of the 132 mobile facets found between the fixed proximal and distal anchors. An additional 10 facets spontaneously fused proximal to the most proximal instrumented implants.

CONCLUSIONS

Implantation of a modern Luque construct with TGV allows for spinal growth in a nonscoliotic animal model. Implant loosening was likely mechanical as no signs of reactive inflammatory reaction were found. Reduction of heterotrophic ossification and spontaneous facet arthrodesis remains a challenge in the management of immature spine.

Biomechanical Evaluation of a Growth-Friendly Rod Construct

BACKGROUND

Distraction-type rods mechanically stabilize the thorax and improve lung growth and function by applying distraction forces at the rib, spine, pelvis, or a combination of locations. However, the amount of stability the rods provide and the amount the thorax needs is unknown.

METHODS

Five freshly frozen and thawed cadaveric thoracic spine specimens were tested for lateral bending, flexion/extension, and axial rotation in displacement control (1°/sec) to a load limit of ±5 Nm for five cycles after which a growth-friendly unilateral rod was placed in a simulated rib-to-lumbar attachment along the right side. The specimens were tested again in the same modes of bending. From the seven Optotrak Orthopedic Research Pin markers (Northern Digital Inc., Waterloo, Ontario, Canada) inserted into the top potting to denote T1, and the right pedicles at T2, T4, T5, T8, T9, and T11 and the Standard Needle Tip Pressure Transducers (Gaeltech, Isle of Skye, Scotland) inserted into the T4/T5 and T8/T9 discs, motion, stiffness, and pressure data were calculated. Parameters from the third cycle of the intact case and the construct case were compared using two-tailed paired t tests with 0.05 as the level of significance.

RESULTS

With the construct attached, the T1-T4 segment showed a 30% increase in neutral zone stiffness during extension (p = .001); the T8-T12 segment experienced a 63% reduction in the in-plane range of motion during flexion (p = .04); and the T8/T9 spinal motion unit had a significant decrease of 24% in elastic zone stiffness during left axial rotation (p = .04).

CONCLUSIONS

It is clear the device as tested here does not produce large biomechanical changes, but the balance between providing desired changes while preventing complications remains difficult.

EVALUATION OF THE RESULTS OF THE USE OF VEPTR IN PATIENTS WITH SCOLIOSIS

ABSTRACT Objective: Evaluation of the results of the use of VEPTR (Vertical Expandable Prosthetic Titanium Rib - Synthes Spine Co.(r), West Chester, Pennsylvania, USA) as an option in spinal instrumentation without fusion in younger children with scoliosis, considering the complications inherent to spinal fusion in this age group. Methods: Sixteen (16) patients with scoliosis, regardless of etiology, with a mean age of 5.2 (3-8) years, were followed up by Spine Surgery Group at Hospital Getúlio Vargas, Recite-PE, and were submitted to surgical correction of the deformity using VEPTR, from April/2009 to July/2014. The survey was conducted through medical register review, and photographic and radiographic records, with the measurement of pre- and postoperative curves by the Cobb method. Results: The mean values of Cobb angle in the preoperative period, in the immediate postoperative period and after the last distraction were, respectively, 84.1° (112°-60°), 55.4° (92°-16°) and 64.4° (100°-16°), with an average initial correction of 28.7° (34.1%) and final correction of 19.7° (23.4%). The mean follow-up was 23.1 (0-61) months with an average distraction of 3.1 (0-8). The complication rate in this study was 62.5%. Conclusion: The VEPTR presented considerable correction rates of scoliosis curves in patients whose age contraindicate the spinal fusion methods. It is necessary to improve the technique and the implant itself in order to reduce complication rates, which can be considered relatively high, in addition to the conduction of more studies with longer follow-up to determine the actual efficacy of the implant and the maintenance of long-term correction.

Use of Vertical Expandable Prosthetic Titanium Rib (VEPTR) in the Treatment of Congenital Scoliosis Without Fused Ribs

BACKGROUND

Although the vertical expandable prosthetic titanium rib (VEPTR) has been shown to be useful in treating congenital scoliosis (CS) with fused ribs, no studies to date have specifically evaluated the efficacy of VEPTR in the treatment of CS without fused ribs. The purpose of this study was to determine the effectiveness of VEPTR in sagittal/coronal curve correction and spine growth and compare its complication rate to the use of VEPTR in other conditions and to other treatment methods used for CS.

METHODS

A multicenter database was queried for patients with CS without fused ribs treated with VEPTR. Anteroposterior (AP) and lateral radiographs were used to measure parameters at 3 timepoints (preoperative, immediate postoperative, and latest follow-up): coronal Cobb angle, sagittal kyphosis, and thoracic and lumbar spine heights. Clinical data included age, time to follow-up, and complications.

RESULTS

Twenty-five patients (13 females, 12 males) were identified. The average age at implantation was 5.7 years, with an average follow-up of 50 months. Several parameters improved from preoperative to latest follow-up: coronal Cobb angle (69 to 54 degrees, P<0.0001), thoracic spine height (T1-T12) in the AP (13.3 to 15.9 cm, P<0.0001) and lateral (14.8 to 17.4 cm, P=0.0024) planes, and lumbar spine height (L1-S1) in the AP (8.8 to 11.4 cm, P<0.0001) and lateral (9.9 to 11.9 cm, P=0.0002) planes. Kyphosis increased over the study period (36 to 41 degrees, P=0.6). Fifteen patients (60%) had 41 complications (average 2.75; range, 1 to 12). Twenty-eight complications (68%) were device-related, and 13 (32%) were disease-related. The most common complications were infection, wound dehiscence, and device migration. Six complications (15%) altered the course of treatment. Thoracic spine height increased 79% of expected growth.

CONCLUSION

VEPTR is an effective treatment for patients with CS without fused ribs, as evidenced by improved radiographic parameters and increased spinal height, with a complication rate which is high but similar to other methods of treatment.

LEVEL OF EVIDENCE

Level IV-case series.

Treatment of Early-Onset Spinal Deformity (EOSD) With VEPTR: A Challenge for the Final Correction Spondylodesis-A Case Series

STUDY DESIGN

Case Series.

OBJECTIVE

To describe the post-VEPTR (vertical expandable prosthetic titanium rib) treatment changes in early-onset spinal deformity (EOSD), which may influence the final correction spondylodesis.

SUMMARY OF BACKGROUND DATA

The VEPTR device, originally developed for the treatment of congenital rib cage malformation, is nowadays more widely used in the treatment of EOSD. At present, only a few reports describe the possible complications that may occur with repeated lengthening procedures of the VEPTR, thereby making the final spondylodesis more complicated and less satisfactory.

METHODS

X-rays of 5 children treated for EOSD with 2 unilateral VEPTR (each rib to rib and rib to lumbar lamina) were analyzed for curve patterns and Cobb angles before, during, and at the end of VEPTR treatment, and after the final spondylodesis. Intraoperative observations during the spondylodesis, which influenced the possibilities of the curve correction, were documented.

RESULTS

All patients showed a marked decompensation of the frontal balance and a high degree of rigidity of the main curve and the compensatory curves after treatment with the VEPTR device. Because of this spontaneous autofusion of spinal segments, migration of the rib cradles and/or the laminar hook, and a change in the curve patterns, the final fusion had to be longer in all patients than the primary deformity would have intended.

CONCLUSIONS

If an EOSD is treated with VEPTR, the curve progression and, in particular, the development of a high thoracic hyperkyphosis or rotation of the main curve should be critically observed. Autofusion of ribs and vertebral bodies may make the final correction spondylodesis even more challenging and risky for the patient and the end result less satisfactory.

Preliminary comparison of primary and conversion surgery with magnetically controlled growing rods in children with early onset scoliosis

PURPOSE

Non-invasive distraction of magnetically controlled growing rods (MCGR) avoids repeated surgical lengthening in patients with early onset scoliosis, but it is not known how effective this technique is in previously operated children.

METHODS

In a retrospective, multicentre study, the data were obtained for 27 primary (P) patients [mean age 7.0 (2.4-10.7) years at surgery] and 23 conversion (C) patients [mean age 7.7 (3.6-11.0) years at conversion from standard growing rods] with 1-year follow-up.

RESULTS

The mean major curve was 63.9° in the P group and 46.5° in the C group at baseline (preoperatively, p = 0.0009) and 39.5° and 39.6°, respectively, at 1-year follow-up (p = 0.99). The mean percentage change of spinal growth from baseline to 1-year follow-up was 18.3 % in the P group and 6.5 % in the C group (p = 0.007). Comparing the spinal growth from postoperative to 1-year follow-up no statistical difference was observed between the study groups (1.8 % P vs -2.2 % C, p = 0.09).

CONCLUSIONS

Scoliosis can be equally controlled after conversion from traditional growing rods into MCGR, but spinal growth from baseline is less in the conversion patients as compared with the primary group.

LEVEL OF EVIDENCE

III.

Early-Onset Scoliosis: A Review of History, Current Treatment, and Future Directions

Early-onset scoliosis (EOS) is defined as curvature of the spine in children >10° with onset before age 10 years. Young children with EOS are at risk for impaired pulmonary function because of the high risk of progressive spinal deformity and thoracic constraints during a critical time of lung development. The treatment of EOS is very challenging because the population is inhomogeneous, often medically complex, and often needs multiple surgeries. In the past, early spinal fusion was performed in children with severe progressive EOS, which corrected scoliosis but limited spine and thoracic growth and resulted in poor pulmonary outcomes. The current goal in treatment of EOS is to maximize growth of the spine and thorax by controlling the spinal deformity, with the aim of promoting normal lung development and pulmonary function. Bracing and casting may improve on the natural history of progression of spinal deformity and are often used to delay surgical intervention or in some cases obviate surgery. Recent advances in surgical implants and techniques have led to the development of growth-friendly implants, which have replaced early spine fusion as the surgical treatment of choice. Treatment with growth-friendly implants usually requires multiple surgeries and is associated with frequent complications. However, growth-friendly spine surgery has been shown to correct spinal deformity while allowing growth of the spine and subsequently lung growth.

Adolescent idiopathic scoliosis

Adolescent idiopathic scoliosis (AIS) is the most common form of structural spinal deformities that have a radiological lateral Cobb angle - a measure of spinal curvature - of ≥10(°). AIS affects between 1% and 4% of adolescents in the early stages of puberty and is more common in young women than in young men. The condition occurs in otherwise healthy individuals and currently has no recognizable cause. In the past few decades, considerable progress has been made towards understanding the clinical patterns and the three-dimensional pathoanatomy of AIS. Advances in biomechanics and technology and their clinical application, supported by limited evidence-based research, have led to improvements in the safety and outcomes of surgical and non-surgical treatments. However, the definite aetiology and aetiopathogenetic mechanisms that underlie AIS are still unclear. Thus, at present, both the prevention of AIS and the treatment of its direct underlying cause are not possible.

[Treatment of early onset scoliosis : How far can we go?]

BACKGROUND

Recently, inconsistent definitions of early onset scoliosis (EOS) and a wide variety of treatment options have been observed.

OBJECTIVES

To clearly define the term EOS, to depict non-operative and operative treatment options, and to present the limitations of the boundaries of these techniques.

METHODS

Review of the literature, including conference presentations and expert opinions, in addition to personal experiences.

RESULTS

Early onset scoliosis (EOS) refers to spine deformity that is present before 10 years of age, regardless of etiology. All existing operative treatment options share a high risk of complications. Therefore, non-operative treatment should act as a time-buying approach to postpone surgery.

DISCUSSION

Awareness of treatment options and their specific indications, in addition to respecting each patient's individual needs and feasibilities, are crucial for the optimal outcome.

Use of the S-hook for Pelvic Fixation in Rib-Based Treatment of Early-Onset Scoliosis: A Multicenter Study

STUDY DESIGN

Retrospective review.

OBJECTIVE

The purpose of this study was to evaluate how several preoperative variables affect the outcome using the rib-to-pelvis S-hook constructs of a rib-based distraction implant (Vertical Expandable Prosthetic Titanium Rib).

SUMMARY OF BACKGROUND DATA

Rib-to-pelvis fixation with S-hooks is one of the options for distal anchoring of rib-based distraction growing rod construct to control early-onset spinal deformity. Since the initial report, the indications of pelvic fixation with S-hooks have been extended and modified.

METHODS

This is an institutional review board-approved retrospective study of patients who underwent rib-based growing rod system surgery-rib-to-pelvis construct with Dunn-McCarthy S-hook. Data evaluation included history, physical examination, preoperative and postoperative radiographs, surgical variables, and complications.

RESULTS

Sixty-five patients were evaluated; 38 were male and 27 were female. Mean age at initial procedure was 71 months. The mean follow-up was 46 months. There was a statistically significant improvement of the immediate postoperative Cobb angle and the last follow-up Cobb angle (P < 0.0001). Fifty percent of the patients (32/65) had S-hook-related complications. The most common complication was sliding of the S-hook out of the iliac crest, followed by infection, neuropathic pain, distal migration of more than 2 cm, fracture of the hook, and bursitis. The complications were related to the preoperative ambulatory status, the use of end-to-end rod connectors, surgical time, and not positioning the hook over the central one-third of the iliac crest at the initial implantation.

CONCLUSION

The use of the S-hook as a pelvic attachment of the rib-based system is indicated in nonambulatory patients with progressive, early-onset scoliosis curve with a lack of adequate anchor at the lumbar spine. Several technical factors should be considered to reduce the complication rate.

LEVEL OF EVIDENCE

3.

Bacterial colonization of VEPTR implants under repeated expansions in children with severe early onset spinal deformities

PURPOSE

Historically, severe spinal and thoracic deformities in children were treated with early long spinal fusions. This prevented further growth of the spine and thorax and often led to small stiff thoraces. Therefore, growth-retaining implants, like vertical expandable titanium ribs (VEPTR), were developed to stimulate thoracic and spinal growth. To accommodate growth, these implants have to be expanded every 6 months. Infection rates of up to 2 % per procedure are reported. Exchange of implant parts allows analyzing the development of implant-related infections and subclinical colonizations.

METHODS

In this prospective study, all patients undergoing repeat VEPTR expansion procedures at our institution were included. Preoperatively, clinical signs of infection were documented, and blood samples were taken. The removed implants were treated by sonication and microbiologically analyzed. The clinical follow-up was documented.

RESULTS

From January 2009 to May 2012, 39 children with 163 re-operations were included. Four of the 39 patients (10 %) developed clinical apparent infections and had implant removal. These were excluded and analyzed separately. Of 144 procedures, implant parts were eligible for analysis. Implant colonization was detected by sonication in 24 of 144 (16 %) operations in 18 out of 39 (46 %) patients. Repeated detection occurred in 5 (14 %) patients. No risk factors for colonization could be identified.

CONCLUSION

The rate of implant colonization is 4.5 times higher than the rate of manifest infections in VEPTR patients. Colonization may lead to a manifest infection over time. The knowledge of persistent implant colonization may change the treatment algorithm in patients with growth-retaining implants.

Safety and efficacy of instrumented convex growth arrest in treatment of congenital scoliosis

BACKGROUND

Anterior and posterior convex hemiepiphysiodesis is a widely used surgical alternative in the treatment of congenital scoliosis. This procedure has the disadvantage of the need for both anterior and posterior approaches. Furthermore, outcomes may be unpredictable. Posterior convex growth arrest (CGA) with pedicle screws at each segment on the convex side may obviate the need for anterior surgery and provides more predictable outcomes. This study retrospectively evaluates the safety and efficacy of instrumented posterior CGA in congenital scoliosis.

METHODS

Patients who had posterior CGA with convex pedicle screw instrumentation for congenital scoliosis were evaluated retrospectively. Thirteen patients (6 male, 7 female) were included in the study. Preoperative, early postoperative, and last follow-up standing posteroanterior and lateral x-rays were evaluated. Cobb angles were recorded for the instrumented segment (main curve). Global thoracic kyphosis was measured between T2 and T12 on sagittal plane. These values were compared preoperatively, postoperatively, and at last follow-up. The T1-S1 vertical height and the height between the concave side pedicles of the upper and lower end vertebra of the main curve was also determined and recorded as the concave height.

RESULTS

The average follow-up was 56.1±10 months (range, 36 to 74 mo) and the average age of the patients at the time of operation was 64.5±30.1 months (range, 15 to 108 mo). All patients were Risser zero at the time of surgery. The average curve magnitude was 49±10.9 degrees (range, 34 to 68 degrees) preoperatively, 38.3±9.7 degrees (range, 28 to 58 degrees) early postoperatively, and 33.5±12.4 degrees (16 to 52 degrees) at last follow-up. There was a significant difference between the preoperative and early postoperative main curve Cobb angle measurements (P=0.001). The average concave height was 94.2±20.2 mm in the early postoperative period and 104.7±21.7 mm at last follow-up (P=0.003). The average T1-S1 height was 292.1±67.1 mm in the early postoperative period and 363.9±94.5 mm at last follow-up (P=0.005). There was at least ≥5 degrees improvement in 9 of the 12 patients in the follow-up period after the index procedure. In 3 patients, the curve did not change and the correction was maintained. Curve progression was observed in 1 patient due to a technical error. There were no wound infections or instrumentation failures during follow-up.

CONCLUSIONS

Instrumented CGA can safely be used in long sweeping curves of immature spines. Using this technique; thoracotomy, anterior procedure, and 2-stage surgery can be avoided. Moreover, it guarantees some degree of correction in all patients because of the instrumentation effect, eliminating the unpredictable nature of classic CGA.

LEVEL OF EVIDENCE

Therapeutic level IV study.

Use of Rib-Based Distraction in the Treatment of Early-Onset Scoliosis Associated With Neurofibromatosis Type 1 in the Young Child

STUDY DESIGN

This study was an institutional review board-approved retrospective review of a prospectively collected multicenter database for rib-based distraction systems used in the treatment of young children with early-onset scoliosis associated with neurofibromatosis type 1 (NF-1).

OBJECTIVE

To evaluate the effectiveness of rib-based distraction and associated complications in managing scoliosis in the growing child with NF-1.

SUMMARY OF BACKGROUND DATA

Patients with NF-1 commonly have scoliosis with curves that can be dysplastic and progressive and respond poorly to bracing. Rib-based distraction systems have recently been described in the management of these complex patients. The efficacy and complication rate using these systems have not previously been reported.

METHODS

Twelve children with NF-1 and scoliosis who were treated with rib-based distraction systems were identified from a prospectively collected multicenter registry. Preoperative and postoperative Cobb angle and T1-S1 spine height were measured from posteroanterior radiographs. The number of lengthenings, age at implantation, years of follow-up, and complications were also acquired from the registry or patient charts.

RESULTS

Mean age at implantation of the Vertical Expandable Prosthetic Titanium Rib device was 6.34 years. Mean preoperative Cobb angle was 66.3°. Average follow-up was 5.2 years. Mean postoperative Cobb angle was 60.8° after an average of 7.75 lengthening procedures (range, 2-16 procedures). T1-S1 height increased in all patients. There were 17 complications in 8 patients (device migration in 6, wound dehiscence in 3, rod breakage in 2, medical issues in 5, and 1 revision for progression of curve). Of the 17 complications, 10 were grade I, 1 was grade II, and 6 were grade IIA; there were no grade III complications.

CONCLUSIONS

The use of rib-based distraction is an effective and relatively safe method of stabilizing curve progression through growth in severe dysplastic scoliosis associated with NF-1.

Proximal junctional kyphosis and failure after spinal deformity surgery: a systematic review of the literature as a background to classification development

STUDY DESIGN

Systematic review of literature.

OBJECTIVE

To perform a comprehensive English language systematic literature review of proximal junctional kyphosis (PJK) and proximal junctional failure (PJF), concentrating on incidence, risk factors, health related quality of life impact, prevention strategy, and classification systems.

SUMMARY OF BACKGROUND DATA

PJK and PJF are well described clinical pathologies and are a frequent cause of revision surgery. The development of a PJK classification that correlates with clinical outcomes and guides treatment decisions and possible prevention strategies would be of significant benefit to patients and surgeons.

METHODS

The phrases "proximal junctional," "proximal junctional kyphosis," and "proximal junctional failure" were used as search terms in PubMed for all years up to 2014 to identify all articles that included at least one of these terms.

RESULTS

Fifty-three articles were identified overall. Eighteen articles assessed for risk factors. Eight studies specifically reviewed prevention strategies. There were no randomized prospective studies. There were 3 published studies that have attempted to classify PJK. The reported incidence of PJK ranged widely, from 5% to 46% in patients undergoing spinal instrumentation and fusion for adult spinal deformity. It is reported that 66% of PJK occurs within 3 months and 80% within 18 months after surgery. The reported revision rates due to PJK range from 13% to 55%. Modifiable and nonmodifiable risk factors for PJK have been characterized.

CONCLUSION

PJK and PJF affect many patients after long segment instrumentation after the correction of adult spinal deformity. The epidemiology and risk factors for the disease are well defined. A PJK and PJF scoring system may help describe the severity of disease and guide the need for revision surgery. The development and prospective validation of a PJK classification system is important considering the prevalence of the problem and its clinical and economic impact.

LEVEL OF EVIDENCE

N/A.

Perioperative Neurologic Injury Associated With Rib-Based Distraction Surgery

STUDY DESIGN

Retrospective, comparative case series from the study group database.

OBJECTIVES

The primary objective was to report the neurologic injury rate for rib-based distraction surgery and determine whether preoperative diagnosis affects this rate. The secondary objective was to describe these injuries and outcome.

SUMMARY OF BACKGROUND DATA

Posterior distraction-based systems are commonly used to treat early-onset scoliosis. General complication rates for these surgeries are high; however, there are few reports in the literature on neurologic injury after rib-based distraction surgery.

METHODS

This was a retrospective review of the Children's Spine Study Group database from 2004 to 2013. The researchers used the chi-square test to compare the distributions of proportions between diagnoses.

RESULTS

A total of 524 patients were identified and treated with rib-based distraction surgery. The preoperative diagnoses consisted of 222 congenital/structural, 163 neuromuscular, 63 syndromic, 67 idiopathic, and 9 unknown. There were 9 neurologic injuries (7 clinical and 2 neuromonitoring alerts) for a neurologic injury rate of 1.7%. Using the Classification for Early-Onset Scoliosis, 8 patients were classified as congenital and 1 as neuromuscular. The neurologic injury rate in the congenital curves group was 3.6% and was 0.34% in non-congenital curves (p = .005). The proportion of injured patients with an additional secondary diagnosis was 3.82%, compared with 0.82% patients with only a primary diagnosis (p = .01). Eight injuries occurred at initial implantation and 1 at revision surgery. Most were brachial plexus (n = 5) with no complete spinal cord injuries. Four patients required return to surgery and 1 needed intraoperative intervention. At 4.2 years' follow-up, 7 of 9 patients had full resolution of symptoms and 2 patients had residual upper extremity weakness.

CONCLUSIONS

The rate of neurologic injury for patients treated with rib-based distraction surgery was 1.7%. Most injuries occurred with congenital diagnoses and they were more likely in patients with additional secondary diagnoses. These injuries were predominantly to the brachial plexus and generally resolved.

Recent advances in the management of early onset scoliosis

As the undesired results of early spinal fusion have become apparent, "growth-friendly" management methods for early onset scoliosis have been increasing during recent years. Current literature supports the use of repeated corrective cast applications as the initial management for most early onset progressive spinal deformities as either definitive treatment or as a temporizing measure. If casting is not an option or the deformity cannot be controlled via casting, one of the growth-friendly instrumentation techniques is chosen. Growth-friendly surgical methods and implants have been evolving as understanding of the disease improves.